Calipers.



E. M. SEALY.

CALIPERS.

APPLICATION man DEC.3. 19H.

1 174,460, Patented Aug. 6, 1918.

INVENTOR cfk'zerM (Sma l! ATTORNEY ESTER M. SEALY, OF HONOLULU, TERRITORY OF HAWAII.

CALIPERS.

Specification of Letters Patent.

Patented A11 6, 1918.

Application filed December 3, 1917. Serial No. 205,166.

To all whom it may concern Be it known that I, Es'run M. SnALY, a citizen of the United States, residing at Honolulu, in the Territory of Hawaii, have invented certain new and useiul Improvements in Calipers, of which the following is a specification.

This invention relates to an improved pair of calipers and the principal object of the invention is to so construct the calipers that a scale may be associated therewith and to further so construct the calipers that they may include a worm and gear for opening and closing the calipers.

Another object of the invention is to so construct these calipers that through turning of the adjusting worm or screw, the jaws may he opened or closed and as the jaws move, the amount of movement registered upon the scale carried by one of the jaws.

Another object of the invention is to so construct the calipers that they may be formed of sheet metal and assembled with a minimum amount of labor.

This invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a plan view of the improved calipers,

Fig. 2 is a View similar to Fig. 1 showing a slightly modified constritiction oi. the free end portions of the jaws, and

Fig. 3 is a plan view of one of the jaws and the adjusting screw or worm for moving the jaws.

This pair of calipers will be provided with jaws 10 and 11, the jaw 10 for corn venience being termed. the stationary jaw and the jaw 11 the movable jaw. The jaws in Fig. 1 have their free end portions extended to provide arms 12 and in this form, the calipers will be used for interior work such for instance as obtaining the interior diameter of a pipe. In the form shown in Fig. 2, the jaws are continued in the arc oi a circle and have their end portions n'ieeting and in this form, the calipers will be used for external work, such for instance as obtaining the external diameter of a pipe or shaft. These jaws are pivotally connected by a pin 13 which passes through the jaw 10 and through an opening 1.4: formed in the gear head 15 ot' the arm or jaw 11 and i'rom an inspection oi Figs. 1 and 2, it will be seen that the jaw 10 extends beyond the pivot point or pin 13 and terminates in an arcuate scale head 16 which moves across the jaw 11 in operative relation to the indicating mark 17. Therefore when the jaws or arms 10 and 11 are moved toward an open position, the position of the mark 17 with respect to the scale of head 16 will indicate the extent to which the jaws have been opened. 'Jhcreiore the diameter oi the pipe may be ascertained upon the scale. In order to move the jaws and retain the jaws in the adjusted position, there has been provided a turning screw or worm 1S rotatably mounted in a cutout or pocket 1.) formed in the jaw and having its threads engaging the teeth oi the gear head 15. Turning of this screw 18 will move the jaws apart or bring them together according to the direction in which the screw is rotated. It will thus be seen that there has been provided a pair of calipers so constructed that they may be readily opened and closed and held. in the adjusted position and further the extent to which they have been opened, shown upon the scale of the jaw 10.

lVhat is claimed is:-

1. A measuring instrun'ient of the class described, comprising jaws having their end portions pivotally com'lected together, one of said jaws having an iinflicating mark thereon and being provided with a gear head about the pivot pointthereoi and the second gear being extended in overlapping relation to the first. mentioned jaw and terminating in an arcuate scale head moving in operative position on the indicating mark on the first jaw, and a worm screw rotatably mounted in said second jaw and engaging the teeth of the gear head oi the first jaw, rotation of the worm screw imparting movement to the first jaw.

2. A measuring instrument of the charac ter described comprising a pair of jaws pivthe first jaw and holding the same in an ad otally connected together, one of said jaws justed position. 10 being provided With an indicating mark and In testimony whereof I affix my signature the other jaw being extended in overlapping; in presence of two Witnesses.

relation to the first jaw and terminating in ESTER M. SEALY.

an arcuate scale moving in operative rela- Vitnesses:

tion to the indicating mark upon said first GEO. WV. GIFFORD,

jaw, and means for imparting movement to J i R. WILSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

